1. Field of the Invention
The present invention relates to flame resistant moulding compositions comprising polycarbonates and graft polymers which, in addition to good flow properties, exhibit good (notched) impact strength and high chemical resistance with a UL94V-0 classification at 1.5 mm. These moulding compositions are particularly suitable for thin-walled housing parts in the electrical and electronics sector.
2. Description of Related Art
In U.S. Pat. No. 5,120,778, a flame retardant polycarbonate composition having improved impact strength is described, which contains polycarbonate resin, halogenated phthalimide and halogenated oligocarbonate as flame retardants, PTFE (polytetrafluoroethylene) as anti-dripping agent and a graft-modified olefin rubber, the graft-modified olefin rubber being a graft polymer of one or more unsaturated dicarboxylic acids or an acid anhydride thereof on an olefinic copolymer graft base.
From EP 494602 A2, pigmented, non-flame-retardant thermoplastic PC/ABS moulding compositions with 1-9% of a grafted olefinic copolymer are known, the grafted olefinic copolymer being a graft polymer of one or more unsaturated dicarboxylic acids or of the anhydride of the acid(s) on a skeleton comprising an olefinic copolymer.
In U.S. Pat. No. 5,087,524, thermoplastic resin compositions containing aromatic polycarbonate and 0.5-5% of an anhydride-containing modifier are described, but the specific anhydride-containing olefinic terpolymers and the compositions according to the present invention are not disclosed.
From the applications JP 2001294742 A, JP 08188708 A, JP 3212468 B2 and JP 63156850, non-flame retardant polycarbonate compositions containing ethylene-propylene-maleic anhydride copolymers are described.